核医学课件 2016年七年制 双语绪论 基础 核医学仪器

个人简介

谢永双，中共党员，副教授，2004年硕士研究生毕业，2012-2013年曾到美国UCLA大学访问学习

个人简介

广西医科大学核医学教研室教师一附院核医学科副主任医师负责五年制班、本硕班、全英班的核医学教学，主要本硕班、全英班的教学;负责核医学的临床工作

NuclearMedicine

IntroductionNuclearmedicinedepartmentofGuangxiMedicalUniversity

Xieyongshuang

NuclearMedicineDefinitionContentMaincharacteristicHistoryreviewandpresentsituationDefinitionItisadiscipline

thatexploitsthepropertiesradioactiveformsofvariouselementsinthediagnosisandtreatmentofdisease.MainContentsExperimentalNuclearMedicineClinicalNuclearMedicineRadionuclidetracingtechniqueRadionuclidedynamicanalysisInvitroradioassayRadioautographyandactivationanalysis

ExperimentalNuclearMedicinediagnosticnuclearmedicinetherapeuticnuclearmedicine

ClinicalNuclearMedicineNuclearMedicineExperimentalnuclearmedicineClinicalnuclearmedicine

TracingtechniqueDynamicanalysisInvitroradioassayRadioautographyActivationanalysisDiagnosisTherapyInvivoInvitroImagingFunctionExternalirradiationinternalirradiationRadioimmunoassayImmunoradiometricassayNuclearMedicineInimaging

theradiopharmaceuticalsaredetectedbyspecialtypesofcamerasthatworkwithcomputerstoprovideveryprecisepicturesabouttheareaofthebodybeingimaged.NuclearMedicineimagingNuclearMedicineIntreatment,theradiopharmaceuticalsgodirectlytotheorganbeingtreated.

Maincharacteristicofnuclearmedicinestructureandfunctionimagingidentifyabnormalitiesveryearlier

thanotherdiagnostictestBeingsafe,painless,andcost-effectiveCharacter

Bothstructureandfunction.

CharactermoreealierCharactermoresafetyHistoryreviewandpresentsituationNuclearMedicine核医学是一门年轻的学科，从1896年发现放射现象至今也只有114年的历史，而从核医学的起源到现在仅几十年，真正形成核医学学科的历史则更短。

Becquerel1896年法国物理学家Becquerel发现了铀的放射性，第一次认识到放射现象。他在研究铀盐时，发现铀能使附近黑纸包裹的感光胶片感光，由此断定铀能不断地发射某种看不见的，穿透力强的射线。1903年与Curie夫人共获Nobel物理学奖。

HistorylookbackMarieS.Curie

1898年在巴黎的波兰化学家Curie(1867-1934)与他的丈夫Pierre共同发现了镭（即88号元素），他们从30吨沥青铀矿中提取了2mg镭。此后，又发现了Pu和Th天然放射性元素。1903年Curie与Bequerel共获Nobel物理学奖，1911年又获得Nobel化学奖。

HistorylookbackDanlos(1844-1912)

1901年法国医师Danlos将放射性镭与结核的皮肤病变接触，试图治疗皮肤病，可以说是第一次医学应用。

HistorylookbackThefatherofclinicalnuclearmedicine1926年美国Boston内科医师

Blumgart首先应用放射性氡研究循环时间，第一次应用了示踪技术（将氡从一侧手臂静脉注射后，在暗室中通过云母窗观察其在另一手臂出现的时间，以了解动-静脉血管床之间的循环时间），后来他又进行了多领域的生理、病理和药理学研究。被誉为”临床核医学之父”。

HistorylookbackThefatherofexperimentalnuclearmedicine

美国化学家Hevesy，最早将同位素示踪技术用于植物的研究、人体全身含水量等生理学研究，并发明了中子活化分析技术。于1943年获得了Nobel奖金。并被称为Thefatherofexperimentalnuclearmedicine。

HistorylookbackErnestLawrence1930年美国加州大学校园里，物理学家ErnestLawrence生产出一个回旋加速器，并生产出多种同位素。1936年，他的兄弟，内科医师JohnLawrence首先用P-32治疗白血病。1939年获物理奖。

HistorylookbackModerncyclotronIreneCurie&FredericJoliot1934年，法国放射化学家Curie和她的丈夫Joliot用a粒子照射Al产生放射性30P,第一次用人工核反应方法生产出放射性核素。同年Fermi等人用中子源轰击靶核生产出多种核素。DavidKuhl1952年美国Pennsylvania大学一年级医学生DavidKuhl设计了扫描机光点打印法。1959年他又用双探头的扫描机进行断层扫描，并进一步研制和完善断层显像仪器，使得SPECT和PET成为核医学显像的主要方法。1996年获得了“

Cassenaward”，被称为Thefatherofemissiontomography。可以认为，没有他的远见，核医学有可能不会发展成为具有特色的专业。

HistorylookbackThefatherofemissiontomographyAnger

andγcamera1957年Anger研制出第一台γ照相机，称之为Anger照相机，1963年在日内瓦原子能和平会议上展出。它克服了逐点扫描打印的不足，使核医学显像走向现代化阶段。HistoryreviewBerson&Yalow1960年美国的Berson和Yalow将核技术与免疫学技术相结合建立了放射免疫分析法，并首先用于测定血浆胰岛素浓度，由于该法对医学的巨大贡献，1977年Yalow获得了NobelPrize。YalowBersonHistoryreviewRadioimmunoassay显像仪器的发展：

直线扫描机γ照相机SPECT

符合线路SPECTPETCT/PET与

CT/SPECT。核医学的现状与进展分子核医学的形成：应用核医学示踪技术从分子水平认识疾病，为临床诊断、治疗和疾病的研究提供分子水平信息甚至分子水平的治疗手段。使医学影像技术走向“分子影像”时代。核医学的现状与进展Molecularnuclearmedicine受体密度与功能基因的异常表达生化代谢变化细胞信息传导临床诊断临床治疗疾病研究提供分子水平信息分子水平治疗手段分子核医学的形成分子影像学的形成治疗核医学的形成与发展

1901年镭结核性皮肤病灶

1903年镭近距离肿瘤治疗

1905年镭突眼性甲状腺肿……1939年

32P白血病

1942年

131I甲状腺功能亢进症……

核医学的现状与进展治疗核医学的形成与发展

核素治疗与化疗、放疗的本质区别：利用核射线治疗疾病治疗药物对病变组织具有选择性治疗作用持久方法安全、简便

核医学的现状与进展治疗核医学的形成与发展

发展方向：放射性核素的研究携带放射性核素的载体研究

具有前景的研究领域：放射免疫靶向治疗受体介导的靶向治疗放射性核素基因治疗放射性核素微粒肿瘤组织间定向植入治疗

核医学的现状与进展BasicPhysicsofNuclearKLMAtomneutronsprotonsnucleon+electrons- ConfigurationofAtomAtomNucleusProtonQuark10-8cm10-12cm10-13cm<10-16cmshellBasicconceptIsotope:Therearethesameprotons,but

differentmassnumber(orneutrons).Isomer:

Therearethesameprotons,neutronsandelectrons;however,theycontainadifferentamountofnuclearenergy.Nuclide:

anuclideisanyindividualatomicspecies,whichcanbedistinguishedbyitsatomicweight,

atomic

number,andatomicenergystate.Stable&radionuclide★Stablenuclidewillnotdecay.Approximately280ofthenuclidesareinastableform.★Radionuclidesareunstableand

spontaneouslyreleaseenergyorsubatomicparticlesinanattempttoreachamorestablestate.Thereareapproximately1500radionuclides.NucleardecayTherearefivekindsofnucleardecay:AlphaDecayBetaDecay(NegativeBetaDecay)PositronEmission(PositiveBetaDecay)GammadecayElectron(orK)CaptureorinternalconversionNucleardecayAlpha(α)decay

Alphaparticlesisaheliumnucleiconsistingof2protonsand2neutrons.4HeγCharacteristicofalphaparticleαdecayoccursinNuclideofP>82.Velocityofαparticleis20thousandkm/sinvacuum.Itcanbeblockedoffbyapaper,sincetheflightofαparticleisshort.Ionizationismorethan

βparticleBetadecayEmitβparticlesandcaptureorbitalelectrons.Tobeacompaniontoincreaseordecreaseofatomicnumber,butthemassnumberofthenewnucleiisthesame.Includingβ－,β＋andelectroncapture.

Velocityofβparticleis200thousandkm/sinvacuum.Penetrabilityismorethanalphaparticle.β-

decayEmitβ－particlesNeutronrichnucleiNeutronprotonThemassnumberofnewnucleiisthesameastheparentnuclei,

atomicnumberincrease1np+β－

+Qβ－γβ＋

decayEmissionofβ＋particleNeutronpoornucleiAprotontoneutrontransformationArtificialradionuclideβ＋γpn+e+189F—188O+β＋

++0.66MeVElectroncapture,ECAnorbitalelectroniscapturedtoformaneutron.NeutronpoornucleiAprotontoneutronP+e-nCharacteristicX-rayAugerelectronγGammadecayandinternalconversionGammadecaymaybeapartofanotherdecayprocess,suchas,ECor-Metastabletostablestatetransitionandemissionofelectromagnetic(γtransition)Newnucleimassandprotonisthesame,butenergychangedInternalconversionandInternalconversionelectronInternalconversionelectronγrayGammadecayandinternalconversionWhenthenucleusmovesfromahighertoalowerenergy,eitheragammarayisproducedorthedeexcitationenergyisusedtoejectanorbitingelectron.Thislatterprocessiscalledinternalconversion.Thisorbitingelectroniscalledinternalconversionelectron(IE).

CharacteristicofγrayGammarayisphotonNoelectricchargePenetrabilityismorethanchargedparticleLowionizationabilityComparisonofthreedecayalphadecaybetadecaygammadecayMasschangedyesnonoProtonchangedyesyesnoEnergychangedyesyesyesThenumberofatoms(N)ofagivenoriginalpopulation(No)whichwillremainafteragiventimeinterval(t)canbecalculatedbytheequation:N=Noe-λtThelawofnucleardecay

ThelawofnucleardecayDecayformula：N=Noe-λtDecayconstant

：Decayconstantequalstofractionofnucleidecayingperunittime.Characteristic：everyradionuclidehasdifferentλ.Commonness：Thisisthebasicexponentialequationforradioactivedecay.Thisisthebasicexponentialequationforradioactivedecay.Ifdesired,theequationalsocanbewrittenintermsofradioactivity(A).A=Aoe–λtA0Thelawofnucleardecay

HalflifePhysicalhalflife，(T1/2)

thetimeittakesforonehalfoftheoriginalnumberofatomstodecay.

ThelongestT1/2>1010a.TheshortestT1/2

<10-10s.

T1/2=0.693/λ

Whenhalfoftheradiopharmaceuticalwithinthebodyremains,thistimeiscalledthebiologicalhalftime.Biologicalhalflife

Effectivehalflife：Thecombinationofthephysicalhalflifeandthebiologicalhalflifeiscalledtheeffectivehalflife.ThusTeffwillbelessthaneitherthebiologicalorthephysicalhalflife.

RadioactivityActivityisthenumberofatomsdecayingperunittime.Onebecquerel(Bq)equalsonedisintegrationpersecond.

acurie(Ci)

is3.7x1010

BqOtherunit：KBq、MBq、GBq，Ci、mCi、Ci。Interactionofrayandmatter

InteractionofchargedparticleandmatterIonizationandexcitationIonization：α、β→matter→electrons→e-leaveorbit→freeelectron；Chargedparticlee-IonpairsSecondaryionization33.85eVmatter

Excitation：

αandβ→matter→orbite-andgotenergy→low

level→highlevel→excitationstate→deexcitation→CharacteristicX-rayandAugerelectron

Chargedparticleparticleγ(deexcitation)BremsstrahlungAnelectrontraversingamaterialmaycomecloseenoughtothenucleusofanatomthatitissharplydeflectedinitspathduetoitsattractiontotheprotons.Thisaccelerationoftheelectronmayproducewhatistermedabremsstrahlungphoton.

particleX-rayScatteringscatteringisaclassofphenomenabywhichparticlesaredeflectedbycollisionswithotherparticles.particleparticleAnnihilationradiationThepositronisemittedwithacertainamountofkineticenergythatitlosesasitmovesthroughitsenvironment.Whenitcomestorest,itannihilateswithanearbyelectrontoproducetwo511keVannihilatingphotonsmovinginoppositedirections.Thisprocessiscalledannihilationradiation.InteractionofphotonandmatterphotoelectriceffectInphotoelectricabsorption,aphotoninteractswiththeatom,losingallitsenergyintheprocess.Aninnershellelectron(usuallyaKshellelectron)isejectedfromtheatom.Theprocessiscalledphotoelectriceffect.

XrayAugerelectronphotoelectronγKLElectronvacancyfilledMe-IncidentphotonPhotoelectriceffectComptoneffectEnergyrange：Severalto0.5MeVPartenergygiveorbitalelectronsResidualenergygivescatteredphotonIncidenceγComptone-scatteringγElasticcollisionKLMElectronpairproductionPhotonenergygreaterthan1.02MeVpassesnearthehighelectricfieldofthenucleusincidenceγγγ511keV511keV+e-freeelectrone-e+NuclearMedicineInstrumentationNuclearMedicineInstrumentationWhatisNuclearMedicineInstrumentation?Howdoesitwork?1.conceptionNuclearmedicineinstrumentationisessentialfornuclearmedicineclinicalpracticeandresearch.imaginginstrumentationnon-imaginginstrumentationIntroductionBasicprinciple

interactionofrayandmatter

Chargedparticle:ionization,

excitation

γphoton:photoelectriceffect

electronpaircomptoneffect

Basicconfiguration

Radiationdetector

theenergyofthegammaphotontothepulsesofelectricalcurrenttransformation.Electronicspart

differentdevicefordifferentneed.Schematicdiagramof

scintillationdetectorconfiguration

Scintillationdetector

Electroniccircuitry

Recordingdevice

Scaler

Countratemeter

Imagingequipment

Scintillationcounter

Functiondeterminationdeviceγcamera、ECTMainlytypeofdetectorTherearemanykindsofdetector.γScintillationdetector

arethemostimportantintracerimaging.γScintillationdetectorAradiationdetectorofthetypeutilizedinnuclearmedicinebasicallyactsasatransducerwhichtransformsincomingradiation(gammaphotons)intovisiblelight(lightphotons).Thisisthepropertywhichmadetheseradiationdetectorsknownasγscintillationdetector.γScintillationdetectorNaI(Tl)crystalPhotomultiplier(PMT)Pre-amplitierImaginginstrument

γCamera

SPECTPETCoincidencecircuitSPECT

GammaScintillationCameraThemaininstrumentfornuclearmedicineimagingisthelargefieldofgammacamera,Firstdevelopedin1956byHalAnger.thisdevicehasbecomethemainimagingtoolofnuclearmedicine.GammaScintillationCameraItisconsistsof:aleadcollimator;ascintillationcrystal;anarrayofphotomultipliertubesonthecrystal;apositioninglogicnetwork;apulseheightanalyzer;andanimagerecordinganddisplaydevice,whichistypicallyacomputersystem.GammaScintillationCameraTomographydevice

ECT：Emissioncomputedtomography

SPECT:singlephotonECT

(one-head,two-head)

PET:positronemissiontomography

SPECTSPECTisperformedwitharotatingAngercameramountedonaspecialgantrythatallows360-degreerotationaroundthepatient.One-headSPECTMostmodernimagingdeviceshavetheabilitytodemonstrateinternalstructuresorfunctinalinformationasasectionalsliceTwo-headSPECT

GEtwo-headSPECTtomographyWholebodyimaging

Siemenstri-headSPECTSPECTimaging

ComparisonofECTandCT,MRI

ECTimagingisfunctionandstructureimaging,butstructureimagingisn’tclearlikeCT,MRIimaging.CT,MRIimagingisstructureimaging.ECTimagingshowsacrosssectionofabodywithadistributedradiopharmaceuticalemittingγ-ray.CTimagingshowsacrosssectionofabodywithaexternalsourceemittingX-ray.CoincidencecircuitSPECTSPECTsystemsusedwithoutcollimatorsinacoincidencemodeiscoincidencecircuitSPECTwhichcanbeusedtodetectthetwo511-keVannihilationphotons.PETOneofthemostexcitingtomographictechniquesispositronemissiontomographyscanning.Positronemittingradionuclidesareusedwiththistechnique.原理

采用一系列成对的互成180度排列后接符合线路的探头，在体外探测示踪剂所产生之湮没辐射的光子，采集的信息通过计算机处理，显示出靶器官的断层图象并给出定量生理参数。SiemensPETPETPETPETtracersDecaysbyemittingapositr